interface IntStart {
    orbitRadius: number;
    radius: number;
    orbitX: number;
    orbitY: number;
    timePassed: number;
    speed: number;
    alpha: number;
    draw: () => void;
}

let WowJs: any = null;
if (typeof window !== 'undefined') {
    const { WOW } = require('wowjs');
    WowJs = new WOW(
        {
            boxClass: 'wow',
            animateClass: 'animated',
            offset: 150,
            mobile: true,
            live: false,
        }
    )
}


const initStars = () => {
    var canvas = document.getElementById('canvas') as HTMLCanvasElement,
        ctx = canvas.getContext('2d') as CanvasRenderingContext2D,
        w = canvas.width = window.innerWidth,
        h = canvas.height = 1300,
        // h = canvas.height = window.innerHeight,
        hue = 217, //星星颜色
        stars:IntStart[] = [],
        count = 0,
        // maxStars = 1400; //星星数量
        maxStars = 200;
        if(window.innerWidth < 1800){
            h = canvas.height = 1150
        }
        if(window.innerWidth < 1400){
            h = canvas.height = 950
        }
        if(window.innerWidth < 1000){
            h = canvas.height = 800
        }


    let canvas2: any;
    if((window as any).canvas2){
        canvas2 = (window as any).canvas2;
    }else{
        canvas2 = document.createElement('canvas');
        (window as any).canvas2 = canvas2;
    }
    
    
    let ctx2: any = canvas2.getContext('2d')
    canvas2.width = 100;
    canvas2.height = 100;

    let half = canvas2.width / 2,
    gradient2 = ctx2.createRadialGradient(half, half, 0, half, half, half);

    gradient2.addColorStop(0.025, '#fff');
    gradient2.addColorStop(0.1, 'hsl(' + hue + ', 33%, 61%)');
    // gradient2.addColorStop(0.1, 'rgba(255,255,255,0.7)');
    // 
    gradient2.addColorStop(0.25, 'hsl(' + hue + ', 64%, 6%)');
    // gradient2.addColorStop(0.25, 'rgba(12,0,0,0.1)');
    gradient2.addColorStop(1, 'transparent');

    ctx2.fillStyle = gradient2;
    ctx2.beginPath();
    ctx2.arc(half, half, half, 0, Math.PI * 2);
    ctx2.fill();

    var Star:any = function (this: IntStart) {

        this.orbitRadius = random(maxOrbit(w, h));
        this.radius = random(60, this.orbitRadius) / 20;
        this.orbitX = w / 2;
        this.orbitY = h / 2;
        this.timePassed = random(0, maxStars);
        this.speed = random(this.orbitRadius) / 600000;
        this.alpha = random(2, 10) / 10;

        count++;
        stars[count] = this;
    }

    Star.prototype.draw = function () {
        var x = Math.sin(this.timePassed) * this.orbitRadius + this.orbitX,
            y = Math.cos(this.timePassed) * this.orbitRadius + this.orbitY,
            twinkle = random(10);

        if (twinkle === 1 && this.alpha > 0) {
            this.alpha -= 0.05;
        } else if (twinkle === 2 && this.alpha < 1) {
            this.alpha += 0.05;
        }

        ctx.globalAlpha = this.alpha;
        ctx.drawImage(canvas2, x - this.radius / 2, y - this.radius / 2, this.radius, this.radius);
        this.timePassed += this.speed;
    }

    for (var i = 0; i < maxStars; i++) {
        // console.log(new Star())
        new Star();
    }

    function animation() {
        ctx.globalCompositeOperation = 'source-over';
        ctx.globalAlpha = 0.8;
        // ctx.fillStyle = 'hsla(' + hue + ', 64%, 6%, 1)';
        let grad = ctx.createLinearGradient(0,0,0,h);
        // linear-gradient( 180deg, #000000 0%, #271D90 66%, #6F7EB7 100%);
        grad.addColorStop(0,'#111')
        grad.addColorStop(1,'#271D90')
        
        
        // grad.addColorStop(1,'#6F7EB7')
        ctx.fillStyle = grad;
        ctx.fillRect(0, 0, w, h)
      
      ctx.globalCompositeOperation = 'lighter';
    //   if((window as any).canvas2){
    //         return;
    //     }
      for (var i = 1, l = stars.length; i < l; i++) {
        stars[i].draw();
      };  
      
      window.requestAnimationFrame(animation);
    }
    animation()
}

function random(min: number, max = 0) {
    if (arguments.length < 2) {
        max = min;
        min = 0;
    }

    if (min > max) {
        var hold = max;
        max = min;
        min = hold;
    }

    return Math.floor(Math.random() * (max - min + 1)) + min;
}
function maxOrbit(x: number, y: number) {
    var max = Math.max(x, y),
        diameter = Math.round(Math.sqrt(max * max + max * max));
    // 星星移动范围，值越大范围越小
    return diameter / 2;
}

export { WowJs , initStars } 
